Question

A mixture contains 4 fluid ounces of water for every 3 fluid ounces of blue food coloring.

How much blue food coloring needs to be added to 12 fluid ounces of water?

A. 3 fl oz
B. 9 fl oz
C. 12 fl oz
D. 16 fl oz

Answer 1

4 / 3 = 12 / x......4 oz water to 3 oz blue = 12 oz water to x oz blue
cross multiply because this is a proportion
(4)(x) = (12)(3)
4x = 36
x = 36/4
x = 9 <=== 9 oz of blue food coloring are needed

Answer 2

divide 12 by 4: 12/4 = 3

now multiply that by 3ounces of food coloring

3*3 =9 fluid ounces are needed,